ll  B  R.AR.Y 

OF  THE 

UNIVERSITY 
OF    ILLINOIS 


G30.T 


Co  p. 


AGRICIH.TURE 


CHECK  FOR  UNBOUND 
CIRCULATING  COPY 


UNIVERSITY  OF  ILLINOIS 

Agricultural  Experiment  Station 


BULLETIN  No.  299 


THE    EFFECTS    OF    PHOSPHORUS    AND 

SULFUR  FERTILIZERS  ON  FLOWER 

PRODUCTION  OF  ROSES  AND 

CARNATIONS 

By  F.  F.  WEINARD  and  P.  A.  LEHENBAUER 


URBANA,  ILLINOIS,  NOVEMBER,  1927 


SUMMARY 

Acid  phosphate  used  with  manure  in  greenhouse  soil  at  the  rate 
of  40  pounds  to  100  square  feet  of  bench  increased  the  yields  of  Hoosier 
Beauty,  Ophelia,  Killarney,  and  White  Killarney  roses  approximately 
6  to  10  percent  in  a  three-year  test.  The  average  increase  was  about 
250  flowers  from  100  plants.  The  fertilizer  cost  was  about  65  cents. 

In  a  one-year  test  on  a  smaller  scale  with  Premier  roses,  the 
yield  with  acid  phosphate  (25  pounds  to  100  square  feet  of  bench) 
was  25  percent  greater  than  from  the  control  plot. 

Steamed  bone  was  not  so  effective  in  increasing  flower  produc- 
tion as  was  acid  phosphate.  This  was  true  when  equal  money  values 
of  the  two  materials  were  applied  (21.4  pounds  of  steamed  bone  to  40 
pounds  of  acid  phosphate),  as  well  as  when  the  two  materials  were 
applied  at  such  rates  as  to  carry  approximately  equivalent  amounts  of 
available  phosphorus  (31.5  pounds  of  steamed  bone  to  25  pounds  of 
acid  phosphate.) 

The  residual  effects  of  steamed  bone  meal  were  more  marked 
than  those  of  acid  phosphate.  However,  under  ordinary  conditions  of 
fertilizer  practice  in  the  greenhouse  the  difference  would  be  of  slight 
practical  importance. 

Acid  phosphate  owes  its  effectiveness  in  a  soil  for  roses  to  the 
phosphorus  and  not  to  the  sulfur  it  carries.  This  is  shown  by  the  fact 
that  the  average  yields  of  Premier  roses  for  two  years  were  about  12 
percent  higher  with  acid  phosphate  than  with  steamed  bone  meal  and 
gypsum.  Furthermore  the  yields  with  steamed  bone  meal  and  gypsum 
averaged  about  5  percent  higher  than  with  gypsum  alone. 

In  the  first  experiment  with  carnations  acid  phosphate  used  at 
the  rate  of  40  pounds  to  100  square  feet  of  bench  with  Champion  and 
White  Enchantress  resulted  in  crop  increases  of  about  6  percent,  or 
one  flower  to  a  plant.  In  later  experiments  with  Laddie  carnations 
apparent  increases  as  high  as  7  percent  were  recorded  for  acid  phos- 
phate; the  average  difference  noted  over  three  seasons  was  about  3 
percent.  With  steamed  bone  for  the  same  period  the  average  was  no 
greater  than  from  the  control  plants.  This  was  also  true  of  gypsum. 
Because  of  the  relatively  small  numbers  of  plants  used  in  the  later 
series  of  experiments,  it  is  impossible  to  say  just  what  signficance  these 
results  have.  A  test  with  different  varieties  of  carnations  as  to  their 
responses  to  fertilizer  treatment  was  unsatisfactory  for  the  same  reason. 

No  consistent  relation  was  noted  between  fertilizer  treatment 
and  the  occurrence  of  split  calyces. 


THE    EFFECTS    OF    PHOSPHORUS    AND 

SULFUR  FERTILIZERS  ON  FLOWER 

PRODUCTION  OF  ROSES  AND 

CARNATIONS 

By  F.  F.  WEINARD  AND  P.  A.  LEHENBAUER* 

A  loam  soil  from  blue-grass  sod,  containing  in  mixture  about  one- 
fourth  rotted  cattle  manure,  is  generally  considered  very  suitable  for 
filling  greenhouse  benches.  The  natural  manure  is  particularly  ef- 
fective in  improving  the  physical  conditions  of  soil.  Under  present 
conditions,  however,  many  growers  have  little  choice  as  to  soil,  and 
manure  of  good  quality  is  increasingly  difficult  to  obtain. 

In  most  cases  the  necessity  of  supplementing  natural  manures  with 
commercial  fertilizer  is  no  longer  a  matter  of  question. 

In  the  experiments  described  in  this  bulletin  several  commercial 
phosphate  and  sulfur  fertilizers  were  used  in  the  growing  of  roses  and 
carnations.  The  results  indicate  that  certain  of  these  materials,  particu- 
larly acid  phosphate,  may  be  used  very  effectively  as  a  supplement 
for  cattle  manure. 

Most  cultivated  soils  contain  a  relatively  small  percentage  of 
phosphorus.  Field  experiments  have  shown  that  the  available  phos- 
phorus in  such  soils  is  seldom  sufficient  to  meet  the  ordinary  require- 
ments of  the  growing  crop.  Sulfur  occurs  in  soils  in  even  smaller 
amounts,  as  a  rule,  than  phosphorus,  altho  appreciable  amounts  of  sul- 
fur are  added  to  field  soils  annually  ^in  rainfall.  The  amounts  of  the 
two  elements  taken  up  by  plants  are  essentially  similar.  Field  experi- 
ments have  shown  that  sulfur  also  may  in  some  cases  be  a  factor  lim- 
iting growth. 

Natural  manures  are  primarily  nitrogenous,  and  contain  a  rela- 
tively small  proportion  of  available  phosphorus  but  considerable  sul- 
fur. Thus  greenhouse  soils  are  likely  to  be  deficient  in  phosphorus 
even  tho  manures  are  mixed  in. 

Bone  products  have  been  generally  used  by  florists  as  a  supple- 
mentary source  of  phosphorus,  but  the  supply  is  limited,  and  acid  phos- 
phate, of  which  there  is  a  plentiful  supply,  is  coming  into  wider  use. 


•The  first  experiments  described  were  begun  by  Dr.  F.  W.  Muncie,  formerly 
Associate  in  Floricultural  Chemistry.  From  September,  1917,  until  September, 
1922,  the  work  was  under  the  direction  of  Dr.  P.  A.  Lehenbauer,  formerly  Assist- 
ant Chief  in  Plant  Physiology.  The  later  work  was  directed  by  Dr.  Weinard, 
Assistant  Chief  in  Plant  Physiology. 

79 


80  BULLETIN  No.  299  [November, 

Acid  phosphate  is  made  by  treating  ground  rock  phosphate  with  acid, 
thereby  changing  the  phosphate  into  a  more  soluble  form  and  insuring 
a  more  effective  distribution  in  the  soil.  Commercial  acid  phosphate 
contains  in  addition  to  calcium  phosphate  an  approximately  equal 
amount  of  calcium  sulfate  (gypsum).  Thus  it  is  efficient  as  a  carrier 
of  either  phosphorus  or  sulfur,  depending  on  the  needs  of  the  soil. 

While  a  great  deal  of  information  has  been  collected  on  the 
effects  of  phosphorus  and  sulfur  fertilizers  with  field  crops,  it  is  im- 
possible for  the  florist  to  apply  this  information  directly  to  his  prob- 
lems, for  conditions  under  glass  differ  widely  from  field  conditions. 
Under  glass  it  is  possible  to  use  to  advantage  a  soil  exceedingly  rich 
in  organic  matter  and  mineral  salts.  Moreover,  the  values  of  the  crop 
increases  obtained  by  the  use  of  fertilizer  are  such  that  cost  places 
practically  no  limit  on  the  amount  that  can  be  economically  used. 

Tests  were  therefore  arranged  in  which  a  number  of  phosphate 
and  sulfur-bearing  materials,  including  acid  phosphate,  steamed  bone 
meal,  precipitated  phosphate,  gypsum,  and  sulfur,  were  used  to  sup- 
plement manure  in  greenhouse  soils. 

WORK  OF  OTHER  INVESTIGATORS 

Lumsden1  increased  the  vigor  of  carnation  plants  with  bone  meaL 
Dorner,  Muncie,  and  Nehrling2  showed  increases  of  5  to  13  percent  in 
flower  production  of  carnations  following  the  use  of  acid  phosphate 
in  comparatively  large  amounts.  The  time  of  cropping  and  the  total 
yields  for  the  season  were  not  affected  by  varying  the  time  of  applica- 
tion of  fertilizers,  that  is,  weekly  applications  as  compared  with  the 
same  amounts  applied  at  four  intervals  approximately  eight  weeks 
apart.  No  definite  relation  was  established  between  fertilizer  treat- 
ment and  splitting  of  calyces,  altho  a  tendency  toward  splitting  was 
noted  when  the  plants  were  underfed.  Muncie,3  working  with  roses, 
obtained  beneficial  effects  with  acid  phosphate  in  amounts  up  to  20 
pounds  per  100  square  feet  of  bench  space,  while  four  times  this 
amount  was  used  without  injury  to  the  plants.  The  increases  in 
flower  production  averaged  about  16  percent.  No  increases  were 
noted  with  potassium  sulfate  under  like  conditions.  Mixing  ground 
limestone  with  the  soil  resulted  in  decreased  production,  regardless  of 
whether  acid  phosphate  was  also  used. 

White4  grew  roses  on  soils  treated  with  raw  bone  meal,  and  with 
a  mixture  of  rock  and  acid  phosphates,  in  comparison  with  untreated 
soil.  During  two  years  of  the  experiment  the  increases  over  the  con- 
trol plot  were  somewhat  greater  where  acid  phosphate  was  used.  Dur- 
ing the  third  season,  when  mineral  phosphate  was  used  on  all  plots, 
no  great  differences  were  to  be  seen. 

Pember  and  Adams5  concluded  that  the  addition  of  acid  phosphate 
at  the  rate  of  about  5  pounds  per  100  square  feet  of  bench  would  give 


1927]  FERTILIZERS  FOR  ROSES  AND  CARNATIONS  81 

good  returns  with  carnations  under  most  conditions,  altho  the  material 
was  used  without  injury  in  amounts  up  to  30  pounds  per  100  square 
feet.  Whether  the  total  amounts  were  added  to  the  soil  at  the  begin- 
ning of  the  season,  or  at  biweekly  intervals  thruout  the  season,  did 
not  seem  to  influence  the  results.  A  noticeable  reduction  in  the  per- 
centage of  split  calyces  occurred  in  those  sections  receiving  nitrogen  in 
comparatively  large  amounts. 

Comprehensive  reviews  on  sulfur  in  relation  to  soil  fertility  have 
been  given  by  Olson  and  St.  John6  and  by  Crocker.7  Further  data 
from  field  experiments  have  been  given  by  Powers.8  In  certain  locali- 
ties, notably  on  the  basaltic  soils  of  Oregon,  sulfur  fertilizers  have 
given  marked  results  with  various  field  crops.  Soils  well  supplied  with 
organic  matter  are  less  likely  to  show  the  need  of  sulfur.  Thus  in 
Pennsylvania,  Ohio,  and  Illinois,  as  pointed  out  by  Stewart,9- 10  little  or 
no  benefit  has  been  derived  from  sulfur  in  various  forms. 

EXPERIMENTS  WITH  ROSES 
Flower  Production  Stimulated  by  Acid  Phosphate 

Because  of  the  very  favorable  results  obtained  in  preliminary  ex- 
periments3 with  relatively  large  amounts  of  acid  phosphate,  a  new 
series  of  tests  with  roses  was  arranged  on  a  larger  scale.  These  and 
subsequent  tests  fully  confirmed  the  results  of  the  earlier  work. 

The  four  benches  in  the  rose  house,  each  100  feet  long,  were 
divided  into  sections  each  four  by  five  feet.  The  sections  were  sep- 
arated by  partitions  consisting  of  two  cross  boards  set  about  one  inch 
apart  to  prevent  leaching  of  soil  and  possible  root  growth  from  one 
section  into  the  next. 

The  benches  were  filled  with  soil,  and  fertilizers  were  added  July 
13,  1916.  One  hundred  pounds  of  well-rotted  manure,  containing 
about  50  percent  moisture,  and  3  pounds  of  dried  blood  were  used  to 
100  square  feet  of  bench.  Acid  phosphate  containing  about  16  percent 
available  phosphoric  acid  was  applied  to  all  even-numbered  sections 
at  the  rate  of  40  pounds  per  100  square  feet.  The  odd-numbered  sec- 
tions received  no  acid  phosphate. 

The  rose  plants  were  set  into  the  benches  on  July  14  and  on 
September  28  all  sections  received  a  top  dressing  of  pulverized  lime- 
stone at  the  rate  of  100  pounds  per  100  square  feet.  On  March  1  and 
May  1  following,  all  sections  received  an  application  of  dried  blood  at 
the  rate  of  3  pounds  per  100  square  feet. 

Manure,  Dried  Blood,  and  Add  Phosphate  Added. — During  the 
summer  months  of  1917  the  plants  were  "dried  off"  by  partially  with- 
holding water  and  then  pruning  back,  following  the  usual  practice  of 
florists.  After  the  plants  had  been  pruned,  the  upper  layer  of  soil  was 
removed,  leaving  approximately  three- fourths  of  the  original  soil.  Fresh 


82  BULLETIN  No.  299  [November, 

soil  that  had  received  rotted  manure  previously  was  then  added  to 
replace  the  soil  taken  out.  After  the  required  amount  of  new  soil  had 
been  added  to  each  section,  dried  blood  was  applied  at  the  rate  of  4 
pounds  to  each  100  square  feet.  At  the  same  time  2  pounds  of  acid 
phosphate  was  put  on  each  section  and,  together  with  the  dried  blood, 
was  worked  into  the  surface  of  the  soil  by  means  of  hand  trowels. 

A  manure  mulch  was  put  on  the  soil  of  each  section  at  the  rate 
of  40  pounds  a  section  on  October  24.  During  the  growing  period 
of  this  season,  as  well  as  the  next,  the  plants  were  fed  with  liquid 
manurea  instead  of  dried  blood,  as  had  been  done  the  season  previous. 

During  the  season  of  1917-18  liquid  manure  was  applied  from 
January  28  to  May  18,  at  intervals  of  approximately  ten  days.  The 
amount  applied  averaged  4.5  gallons  per  section  for  each  application. 
Of  course  the  composition  of  liquid  manure  is  variable. 

Analyses  at  this  laboratory"  indicated  that  liquid  manure  made 
according  to  the  process  described  contains  on  an  average  about  .03 
percent  nitrogen,  .027  percent  phosphoric  acid,  and  .008  percent  potash. 
Thus  the  amount  of  phosphorus  added  in  liquid  manure  would  hardly 
be  sufficient  to  influence  the  phosphorus  requirements  of  the  plants. 

During  the  summer  of  1918  the  roses  were  again  given  a  short 
period  of  rest  by  partially  withholding  water  and  were  pruned  back 
on  July  10.  Again  about  one- fourth  of  the  soil  was  removed  from  the 
surface  of  each  section  and  replaced  with  fresh  soil  which  had  been 
mixed  with  well-rotted  manure  in  the  proportion  of  3  parts  soil  to  1 
part  manure.  The  new  soil  was  put  in  the  benches  on  July  13.  Fer- 
tilizers were  then  applied  to  the  surface  of  the  soil  of  each  section  as 
follows:  5  pounds  dried  blood  and  10  pounds  acid  phosphate  to  100 
square  feet.  No  lime  was  applied  during  this  season.  On  November 
15  a  manure  mulch  was  applied  at  the  rate  of  2  bushels  per  section. 
During  the  growing  season  from  October  28  to  May  2  liquid  manure 
was  again  applied  at  intervals  of  about  12  days  at  an  average  rate  of 
5  gallons  to  each  section. 

The  varieties  used  were  Hoosier  Beauty,  Ophelia,  Killarney,  and 
White  Killarney.  All  the  stock  was  one-year  grafted.  Hoosier  Beauty 

"The  liquid  manure  was  prepared  as  follows:  3  bushels  of  fresh  cow  manure, 
with  sufficient  water  to  cover  well,  were  placed  in  a  325-gallon  tank.  The  mixture 
was  stirred  and  allowed  to  stand  until  fermentation  took  place,  as  was  indicated 
by  the  rise  of  the  manure  to  the  surface  of  the  liquid.  This  required  from  three 
to  five  days.  Water  was  then  added  until  the  tank  was  filled,  which  caused  the 
solid  manure  to  sink  to  the  bottom.  The  liquid  was  then  drawn  off  into  another 
tank.  The  process  was  repeated  with  the  original  manure  and  the  second  lot 
of  liquid  drawn  off  into  the  second  tank.  The  liquid  from  the  two  treatments  of 
the  manure  then  was  applied,  by  means  of  pipe  connections  and  hose,  to  the 
soil.  Equal  amounts  were  applied,  as. nearly  as  possible,  to  each  section. 

bEnglis,  D.  T.  A  study  of  liquid  fertilizers.  Thesis,  University  of  Illinois, 
1916. 


1927]  FERTILIZERS  FOR  ROSES  AND  CARNATIONS  83 

and  Ophelia  occupied  the  two  north  benches  and  Killarney  and  White 
Killarney  the  two  south  benches.  In  the  first  season  two  varieties 
were  planted  to  a  bench  in  longitudinal  rows.  This  arrangement 
proved  unsatisfactory  with  the  first  two  varieties  named  on  account 
of  their  different  moisture  requirements.  The  plants  were  later  reset 
in  rows  across  the  bench,  so  that  the  varieties  occupied  separate 
blocks  in  each  plot. 

In  the  first  season  41  Ophelia  plants  showed  crown-gall  infection 
on  the  shoots.  Galls  were  in  evidence  on  this  variety  to  some  extent 
for  the  remainder  of  the  experiment,  but  none  of  the  plants  were 
noticeably  injured.  The  galled  plants  were  distributed  approximately 
equally  on  the  treated  and  untreated  plots,  and  when  it  was  apparent 
that  no  appreciable  error  would  result,  the  yields  were  included  in  the 
results  from  the  fertilizer  experiment.  The  other  varieties  were  not 
affected. 

Records  of  flower  production  by  individual  plants  were  kept  dur- 
ing the  three  years  from  the  beginning  of  September  until  the  end  of 
May.  The  flowers  were  cut  so  as  to  leave  at  least  two  good  leaves 
above  the  previous  break.  Flowers  with  stems  less  than  4  inches 
in  length  were  not  counted. 

Increases  with  Acid  Phosphate. — Flower  production  was  in- 
creased consistently  each  season,  in  each  variety,  where  acid  phos- 
phate was  used  (Tables  1  and  4).  Detailed  analysis  of  the  dataa 
shows  that  the  differences  were  due  to  the  soil  treatment  and  not  to 
chance.  Great  variation  in  flower  production  by  different  plants  was 
observed.  With  Ophelia  plants  in  1917-18,  for  example,  the  range  was 
from  4  to  45  flowers  to  a  plant.  With  Killarney  in  the  same  year  the 
range  was  from  18  to  62  flowers  a  plant.  These  differences  are  due  in 
part  perhaps  to  actual  differences  in  flowering  capacity  and  in  part 
also  to  location  on  the  bench. 

The  average  yearly  crop  increases  in  three  varieties  for  the  three- 
year  period  of  the  experiment  were:  Ophelia,  2.7  flowers  a  plant  (9.8 
percent) ;  Killarney,  2.2  flowers  a  plant  (6.0  percent) ;  and  White 
Killarney,  2.6  flowers  a  plant  (7.9  percent).  As  has  been  previously 
pointed  out,  Hoosier  Beauty  was  grown  under  unfavorable  conditions 
in  1916-17,  which  no  doubt  accounts  for  the  lack  of  response  to  the 
phosphate  treatment  in  this  season.  During  the  two  subsequent  sea- 
sons definite  increases  averaging  1.9  flowers  a  plant  (13.0  percent) 
were  obtained  in  this  variety  with  acid  phosphate.  In  the  test  with 
Premier  roses  the  increased  yield  with  acid  phosphate  amounted  to 
4.7  flowers  a  plant  (25  percent) .  The  comparative  rates  of  flower  pro- 
duction of  three  varieties  of  roses,  with  and  without  acid  phosphate, 
are  shown  graphically  in  Fig.  1. 


'Appendix,  page  101. 


84 


BULLETIN  No.  299 


[November, 


The  average  length  of  flower  stems  where  acid  phosphate  was  used 
was  equal  to  or  greater  than  the  average  stem  length  from  sections 
where  no  acid  phosphate  was  applied.  The  benefit  from  acid  phos- 
phate was  shown  also  in  the  grading  of  the  flowers  (Table  4) .  Closer 
analysis*  showed  further  that  plants  which  produced  the  most  flowers 
did  not  give  any  undue  proportion  of  short  stems. 

TABLE  1. — EFFECT  OF  ACID  PHOSPHATE  ON  FLOWER  PRODUCTION  OF  ROSES 


Variety 

Season 

Treatment 

Number 
of 
plants 

Flowers  per 
plant1 

In- 
creases 

Average 
stem 
length 

pcrct. 

inches 

Hoosier  Beauty  .  . 

1916-17 

No  phosphate.. 

144 

18.  10+.  28 

13.04 

Acid  phosphate. 

144 

18.20±.33 

0 

13.08 

1917-18 

No  phosphate.  . 

144 

15.00±.25 

13.32 

Acid  phosphate. 

144 

17.01±.31 

13.3 

13.90 

1918-19 

No  phosphate.  . 

144 

13.94±.25 

13.79 

Acid  phosphate. 

144 

15.71±.33 

12.7 

13.95 

Ophelia  

1916-17 

No  phosphate.  . 

144 

32  .  12  ±  .  42 

12  84 

Acid  phosphate. 

143 

35.21±.47 

9.6 

13.07 

1917-18 

No  phosphate.  . 

144 

25.01±  .36 

13.44 

Acid  phosphate. 

143 

27.  68+.  40 

10.7 

14.17 

1918-19 

No  phosphate.  . 

144 

25.57±.38 

13.92 

Acid  phosphate. 

143 

27.S6±.41 

9.0 

14.17 

Killarney  

1916-17 

No  phosphate.  . 

144 

36  .  56  ±  .  69 

8.84 

Acid  phosphate. 

144 

39.20±.60 

7.2 

9.08 

1917-18 

No  phosphate.  . 

144 

36.44+  .44 

9.67 

Acid  phosphate. 

144 

39.  08+.  53 

7.2 

10.44 

1918-19 

No  phosphate.  . 

144 

35.53±  .48 

9.61 

Acid  phosphate. 

144 

36.82+  .60 

3.6 

10.17 

White  Killarney.  . 

1916-17 

No  phosphate.. 

144 

33.  80+.  41 

Acid  phosphate. 

144 

35.90±.48 

6.2 

1917-18 

No  phosphate.  . 

144 

32.89±  .36 

9i20 

Acid  phosphate. 

144 

36.  40  +.49 

10.7 

9.92 

1918-19 

No  phosphate.  . 

144 

34.56±.43 

9.48 

Acid  phosphate. 

144 

36.  87+.  55 

6.7 

10.11 

JThe  "probable  errors"  which  are  placed  after  the  averages  of  flower  production  are  of 
interest  to  those  familiar  with  statistical  methods.  They  indicate  the  reliability  of  the  averages 
and  are  useful  in  determining  the  importance  to  be  attached  to  differences  in  the  results  from 
different  treatments. 


It  is  clear  that  acid  phosphate  is  very  effective  in  soil  used  for 
growing  greenhouse  roses.  Where  acid  phosphate  was  used  as  a  sup- 
plement to  manure,  crop  increases  of  6  percent  and  higher  were  ob- 
tained consistently  with  several  varieties  of  roses.  The  beneficial 
effects  of  the  acid  phosphate  were  not  confined  to  any  one  season, 
but  were  evident  during  the  entire  period  in  which  the  plants  were 
grown. 

In  these  experiments  the  average  increase  in  flower  production 
with  four  varieties  of  roses  was  over  9  percent,  or  more  than  250  flow- 
ers from  100  plants,  as  a  result  of  using  acid  phosphate.  Stem 
lengths  averaged  as  long  or  longer  than  in  the  case  of  flowers  from 
untreated  soil. 

The  net  profits  from  the  crop  increases  were  comparatively  high, 
for  with  acid  phosphate  at  $25  a  ton  the  cost  of  the  fertilizer  for  100 
plants  was  about  65  cents. 

'Appendix,  page  102. 


1927] 


85 


3SO\       I       I     - 


1      I      I      I      I      I 
.Acid  Phosphate 


Ophelia  Roses 


4/x> 


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Killarney  Roses 


Dote-  9/30         /O/3I  11/30         a/31  ifil  2/26  3/31 


4/3O 


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Dote-ifto 


\       \       I      1      1       I 
Acid  Phosphate 


.No  Phosphate 


White  Killarney  Poses 


10/31  ///JO          12/31  1/31 


A 


3/31  4/30        SfS/ 


FIG.  1. — ACID  PHOSPHATE  INCREASED  YIELDS  OF  ROSES 

Flower  production  of  all  three  varieties  of  roses  was  uniformly  higher  with  acid  phos- 
phate. The  differences  were  most  marked  during  the  winter  months  in  each  case.  The  relative 
increases  in  fall,  winter,  and  spring  were  quite  consistent  in  the  three  varieties,  averaging  4 
percent,  12  percent,  and  8  percent  respectively.  The  proportion  of  the  crop  obtained  in  each 
case  during  the  months  of  December  to  February  inclusive  was  little  affected  by  the  fertilizer 
treatment.  About  27  percent  of  the  season's  cut  from  Ophelia,  23  percent  from  Killarney,  and 
20  percent  from  White  Killarney  was  obtained  during  the  winter.  (Experiment  1916-1917) 


86  BULLETIN  No.  299  [November, 

Comparison  of  Phosphatic  Fertilizers 

Since  steamed  bone  is  classed  with  acid  phosphate  as  a  fertilizer 
supplying  phosphorus,  a  comparative  study  was  made  of  these  two 
fertilizers  in  their  effects  on  flower  production.  Steamed  bone  meal 
costs  more  per  ton  than  acid  phosphate,  but  as  it  contains  nitrogen 
and  about  half  again  as  much  phosphorus,  there  is  little  difference  in 
cost  per  pound  of  "plant  food"  in  the  two  materials.  The  general 
opinion  is,  however,  that  the  phosphorus  as  contained  in  acid  phos- 
phate is  the  more  readily  available  to  plants. 

There  are  reasons  why  it  is  not  wise  to  be  content  with  applying 
the  results  of  experiments  with  field  crops  to  general  greenhouse  prac- 
tice. Conditions  of  temperature  and  moisture  in  the  greenhouse  are 
more  favorable  to  bacterial  growth,  and  the  accompanying  decompo- 
sition of  organic  matter  is  so  much  more  rapid  that  the  tri-calcium 
phosphate  of  bone  meal  might  possibly  be  made  available  as  quickly 
as  needed.  The  use  of  bone  meal  by  florists  has  been  so  general  and 
its  favor  so  universal  that  nothing  short  of  actual  demonstration  with 
the  crop  concerned  would  suffice  to  change  floricultural  practice. 

Acid  Phosphate  and  Steamed  Bone  Meal  1916-1917. — Soil  was 
prepared  by  adding  a  liberal  quantity  of  manure.  After  the  benches 
were  filled,  the  acid  phosphate  or  steamed  bone  was  added  and  worked 
into  the  soil.  Acid  phosphate  was  used  at  the  rate  of  40  pounds  per  100 
square  feet  of  bench  space  5  inches  deep.  The  weight  of  the  bone 
meal  used  was  calculated  from  relative  cost  prices  of  the  two  ferti- 
lizers so  as  to  obtain  the  same  money  value.  For  this  purpose  $15  a 
ton  for  acid  phosphate  and  $28  a  ton  for  steamed  bone  were  chosen  as 
representing  fairly  the  stable  pre-war  prices.  Thus  bone  meal  was 
used  at  the  rate  of  21.4  pounds  for  each  100  square  feet  of  bench  space. 
Dried  blood  was  applied  uniformly  over  all  sections  whenever  the  ap- 
pearance of  the  plants  indicated  a  need  of  nitrogen. 

One-year-old  plants  of  Killarney  and  Richmond  roses  were  grown 
in  this  experiment.  They  were  dried  off  and  rested  from  June  1  until 
July  14,  then  removed  from  the  bench,  their  roots  shaken  clean  of 
soil,  and  reset  in  the  new  soil  containing  the  manure,  dried  blood,  and 
the  whole  of  the  quantities  of  acid  phosphate  or  bone  meal  required 
by  the  experiment.  The  Richmond  occupied  18  five-foot  sections  of 
the  two  north  benches  and  the  Killarney  18  sections  of  the  two  south 
benches  in  the  house,  with  16  plants  in  each  section. 

An  individual  record  was  kept  of  each  of  the  576  plants,  so  that 
it  is  possible  to  know  how  many  flowers  each  plant  produced,  the 
date  of  production,  and  the  quality  of  the  flowers  as  measured  by 
length  of  stem  (Table  2  and  Fig.  2.)  Records  were  taken  each 
working  day  from  September  15  to  June  1.  Flowers  were  cut  so  as  to 
leave  at  least  two  good  leaves  above  the  previous  break. 


1927] 


FERTILIZERS  FOR  ROSES  AND  CARNATIONS 


87 


TABLE  2. — YIELDS  OF  ROSES  WITH  ACID  PHOSPHATE  AND  STEAMED  BONE,  1916-1917 


Variety 

Treatment 

Flowers 
per  plant 

Increase 

Average  stem 
length 

Killarney  

Acid  phosphate  

45.20±  .60 

perct. 
29.5 

inches 
10.53 

Steamed  bone  

34.90±  .58 

9.92 

Richmond  

Acid  phosphate  

35.45±  .56 

25.3 

9.76 

Steamed  bone  

28.30±  .39 

9.63 

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Richmond  Poses 


Date-  »/         /o/26      ///a       a/2/        r/fo       z/is        3/is       4/0        sfio 
FIQ.  2. — ACID  PHOSPHATE  MORE  EFFECTIVE  THAN  STEAMED  BONE 

With  both  varieties  of  roses,  the  greatest  differences  in  yields  were  noted  during  the 
fall  and  spring  months,  amounting  to  approximately  40  percent  and  30  percent  with  Killarney 
and  Richmond  respectively.  The  differences  during  the  winter  months  were  about  half  the 
above  figures.  With  acid  phosphate,  about  28  percent  of  the  crop  in  each  case  was  cut  during 
the  months  of  December  to  January  inclusive;  with  steamed  bone,  about  32  percent  of  the 
entire  crop  was  cut  in  the  same  period.  (Experiment  1916-17) 


88  BULLETIN  No.  299  [November, 

Acid  Phosphate,  Steamed  Bone  Meal,  and  Precipitated  Phos- 
phate* 1921-1924. — The  differences  in  flower  production  obtained  with 
acid  phosphate  and  bone  meal  in  the  first  test  were  so  marked  that 
the  experiment  was  repeated.  Precipitated  phosphate,  a  finely  divided 
material  high  in  available  phosphorus,  was  used  also  in  this  series 
of  tests. 

The  plots  were  located  on  the  second  bench  from  the  south  in  an 
east-and-west  house.  The  bench  was  divided  by  cross  partitions  into 
12  plots  which  were  numbered  consecutively  from  west  to  east.  Each 
plot,  with  the  exception  of  No.  6,  was  slightly  over  8  feet  long  and 
contained  28  plants.  Plot  6  was  9  feet  long  and  contained  32  plants. 

The  soil  used  was  a  comparatively  fertile  brown  silt  loam.  Rotted 
cow  manure  was  thoroly  worked  into  the  soil  in  the  field,  approxi- 
mately 1  part  of  manure  being  used  to  4  parts  of  soil  by  volume.  The 
first  season  the  commercial  fertilizers  were  worked  into  the  soil  on  the 
bench  before  setting  the  plants.  At  the  beginning  of  each  subsequent 
season  about  an  inch  of  the  top  soil  was  removed  and  new  soil  and 
fertilizers  were  added  before  the  plants  were  started  into  growth. 

Own-root  rose  plants  of  the  variety  Premier  propagated  the  pre- 
vious winter  were  benched  in  July,  1921,  and  allowed  to  remain  undis- 
turbed for  three  years.  Each  season  beginning  about  the  middle  of 
June  water  was  withheld  sufficiently  to  stop  growth  without  causing 
the  leaves  to  fall.  In  the  latter  part  of  July  the  plants  were  pruned 
and  started  into  growth.  During  the  growing  season  the  temperatures 
maintained  were  58°  F.  at  night  and  68°  F.  by  day.  On  bright  days 
the  temperature  was  allowed  to  rise  to  73-78°  F.  Since  there  was 
sometimes  a  difference  of  several  degrees  in  temperature  between  the 
two  ends  of  the  house,  the  fertilizer  treatments  were  duplicated  at  both 
ends  of  the  bench. 

In  an  effort  to  keep  conditions  as  uniform  as  possible  on  all  plots 
pinching  of  shoots  was  avoided  and  all  flowers  were  allowed  to  develop. 
This  practice  likewise  insured  a  more  accurate  determination  of  the 
natural  tendency  toward  long  or  short  growth  of  stems  under  various 
treatments.  Stems  were  cut  at  the  second  vigorous  leaf  above  the  pre- 
vious break,  except  in  the  case  of  bottom  shoots,  which  were  cut  con- 
siderably higher. 

The  seasons  of  record  on  roses  were  as  follows:  1921-22,  Septem- 
ber 12  to  May  29;  1922-23,  September  18  to  April  30;  1923-24,  Sep- 
tember 26  to  May  10.  With  the  exception  of  Sundays  and  holidays, 
flowers  were  cut  and  stem  lengths  measured  daily.  Data  from  the  out- 
side row  at  either  end  of  the  bench  were  not  used  in  computing  re- 
sults. 


'Precipitated  phosphates  are  now  used  chiefly  in  the  manufacture  of  propri- 
etary animal  feeds. 


1927] 


FERTILIZERS  FOR  ROSES  AND  CARNATIONS 


89 


Each  season  all  rose  plots  received  an  initial  application  of  nitro- 
gen in  the  form  of  dried  blood,  at  the  rate  of  5  pounds  for  each  100 
square  feet  of  bench  surface.  This  was  supplemented  by  a  manure 
mulch  in  the  fall  and  by  feeding  with  liquid  manure  at  biweekly  inter- 
vals in  the  spring. 

The  kinds  and  amounts  of  the  other  fertilizers  applied  each  season 
are  given  in  Table  3.  In  1921-22  the  amount  of  acid  phosphate  used  was 
near  the  optimum  as  shown  by  previous  experiments.  The  precipi- 
tated phosphate  used  contained  a  similar  amount  of  available  phos- 
phorus. The  total  phosphorus  in  the  steamed  bone,  while  almost 


TABLE  3. — KINDS  AND  AMOUNTS  OP  PHOSPHORUS  AND  SULFUR  FERTILIZERS  USED 
WITH  PREMIER  ROSES,  1921-1924 


Plot 

Fertiliier  (pounds  per  100  square  feet  of  bench) 

1 

2 
3 
4 

5 

6 
7 
8 
9 
10 
11 
12 

Steamed  bone  

1921-22 

1922-23 

1923-24 

31.5 
15 
25 
15 
0 
31.5 
0 
0 
25 
31.5 
15 
25 
15 
31.5 

9 

8 
14 
8 
7 
9 
7 
7 
14 
0 
0 
0 
8 
9 

31.5 
15 
25 
15 
11 
31.5 
11 
11 
25 
0 
0 
0 
15 
31.5 

Precipitated  phosphate  

Acid  phosphate  

Precipitated  phosphate  

Gypsum  

Gypsum  

Acid  phosphate  

Steamed  bone  

Precipitated  phosphate  

Steamed  bone  

double  that  in  the  other  materials,  was  present  presumably  in  a  less 
available  form.  In  1922-23  these  amounts  were  varied  and  approxi- 
mately equal  amounts  of  phosphorus  were  applied  in  acid  phosphate 
and  in  steamed  bone.  In  1923-24  the  phosphatic  fertilizers  were  used 
as  in  1921-22. 

Acid  Phosphate  More  Effective  Than  Steamed  Bone  Meal. — 
Acid  phosphate  gave  better  results  than  did  steamed  bone  meal  or 
precipitated  phosphate  (Tables  2  and  4) .  In  the  one-season  test  flower 
production  with  acid  phosphate  exceeded  that  with  steamed  bone  by 
10.3  flowers  a  plant  (29.5  percent)  in  the  case  of  Killarney,  and  by  7.2 
flowers  a  plant  (25.3  percent)  with  Richmond  roses. 

From  this  it  is  clear  that  steamed  bone  meal  proved  less  econom- 
ical as  a  phosphorus  fertilizer  for  roses  than  acid  phosphate.  When 
the  two  materials  were  applied  at  rates  determined  by  equal  money 
value,  about  27  percent  or  over  850  more  flowers  were  obtained  from 
100  plants  where  the  acid  phosphate  was  used. 

In  the  later  test,  yields  the  first  season  were  higher  with  both 
acid  phosphate  and  precipitated  phosphate,  the  increase  being  prac- 
tically 2  flowers  (9  percent)  in  each  case.  In  the  second  season  there 


90 


BULLETIN  No.  299 


[November, 


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Fertilizer 

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phosphate  .... 
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Precipitated 
phosphate.  .  .  . 
(1921  only) 

1927]  FERTILIZERS  FOR  ROSES  AND  CARNATIONS  91 

were  no  significant  differences  between  the  yields  on  the  several  phos- 
phate plots.  In  the  third  season  production  with  acid  phosphate  ex- 
ceeded that  with  either  of  the  other  substances  by  3.2  flowers  a  plant 
(15  percent). 

The  stem  lengths  with  acid  phosphate  and  precipitated  phosphate 
were  slightly  longer  on  the  average  than  with  steamed  bone.  This  dif- 
ference in  stem  lengths  was  also  evident  in  the  grading  of  the  flowers 
(Table  4). 

The  16  percent  of  phosphoric  acid  in  acid  phosphate  is  considered 
relatively  available  for  use  by  plants,  while  perhaps  half  of  the  27 
percent  of  phosphoric  acid  in  steamed  bone  meal  is  available  over  a 
growing  season.  With  this  fact  in  mind  twice  as  much  phosphoric 
acid  in  the  form  of  steamed  bone  meal  was  used  with  Premier  roses  as 
was  applied  in  the  form  of  acid  phosphate.  With  acid  phosphate  at 
$25  a  ton  and  steamed  bone  meal  at  $40,  the  costs  of  the  fertilizer  for 
100  plants  were  about  40  cents  for  the  acid  phosphate  and  twice  as 
much  for  the  steamed  bone.  Yet  about  9  percent  more  flowers  were 
obtained  with  the  acid  phosphate  in  the  first  season,  an  increase  of 
about  190  flowers  from  100  plants. 

In  the  second  season,  when  smaller  amounts  of  fertilizers  were 
used,  there  were  no  differences  between  yields.  Comparatively  large 
amounts  of  acid  phosphate  seem  to  be  necessary  to  produce  heavy 
cropping  of  roses,  and  on  the  other  hand,  the  residual  effects  of  the 
steamed  bone  may  have  been  partly  responsible  for  this  result. 

In  the  third  season,  with  fertilizer  applications  similar  to  those 
of  the  first  season,  an  even  greater  difference  in  yields  was  obtained 
than  in  the  first  season.  With  acid  phosphate  the  crop  of  flowers 
was  about  15  percent  larger.  This  meant  an  increase  of  about  300 
flowers  from  100  plants. 

Add  Phosphate  Most  Effective  When  Applied  Annually. — A 
second  application  of  phosphate  fertilizers  in  1922-23  gave  no 
increase  in  yield,  with  the  possible  exception  of  acid  phosphate,  in  com- 
parison with  plants  which  received  phosphate  the  first  season  only 
(Table  5).  In  the  third  season,  however,  the  increase  in  flower  pro- 
duction by  the  plants  receiving  annual  applications  of  acid  phosphate 
amounted  to  3.9  flowers  a  plant  (19  percent).  In  the  case  of  steamed 
bone  and  precipated  phosphate  there  were  no  differences  in  yield  on 
the  different  plots.  Presumably  this  was  a  result  of  the  residual  effects 
from  a  single  application  of  these  materials. 

With  acid  phosphate  there  was  evidently  a  distinct  advantage  in 
annual  applications  of  the  fertilizer.  With  steamed  bone  or  precipi- 
tated phosphate,  however,  a  single  application  in  the  three-year  period 
proved  about  as  effective  as  repeated  treatments.  Stem  lengths  were 
practically  uniform  with  each  fertilizer. 


92 


BULLETIN  No.  299 


[November, 


CO 

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1927]  FERTILIZERS  FOR  ROSES  AND  CARNATIONS  93 

Altho  the  residual  effects  of  acid  phosphate  proved  to  be  less 
marked  than  in  the  case  of  steamed  bone,  the  value  of  the  crop  in- 
creases from  annual  applications  of  acid  phosphate  was  such  as  to 
repay  the  cost  many  times  over. 

More  frequent  applications  of  acid  phosphate  than  once  each  sea- 
son were  not  tried.  Surface  applications  of  acid  phosphate,  however, 
encourage  the  growth  of  roots  near  the  surface,  where  they  are  subject 
to  drying,  and  the  practice  is  therefore  not  recommended.  On  the  other 
hand,  any  attempt  to  turn  the  material  into  the  soil  during  the  growing 
season  would  result  in  the  destruction  of  active  roots. 

Gypsum  Not  Effective  for  Increasing  Flower  Production 

Gypsum  was  used  on  certain  plots  of  Premier  roses  in  1922-24, 
in  amounts  approximately  equivalent  to  the  gypsum  applied  on  other 
plots  in  acid  phosphate  (Tables  3  and  6). 

The  average  number  of  flowers  cut  in  1922-23  where  acid  phos- 
phate or  steamed  bone  was  used  was  3.8  flowers  (19  percent)  more 
than  with  gypsum.  The  average  with  precipitated  phosphate  was 
higher  by  3.1  flowers  (16  percent)  than  with  gypsum.  Neither  steamed 
bone  and  gypsum,  nor  precipitated  phosphate  and  gypsum,  gave  better 
results  than  steamed  bone  or  precipitated  phosphate  alone.  Again  in 
the  following  season  more  flowers  were  obtained  with  acid  phosphate 
than  with  gypsum,  the  difference  amounting  to  3.9  flowers  a  plant 
(19  percent).  Stem  lengths  were  uniform  thruout. 

The  fact  that  no  benefit  was  obtained  from  the  use  of  gypsum 
in  the  rose  soil  under  the  conditions  of  the  experiment  indicates  that- 
the  beneficial  effects  of  acid  phosphate  were  due  to  the  phosphoric- 
acid  content  rather  than  to  the  sulfate  added  to  the  soil  at  the  same 
time.  Large  amounts  of  cattle  manure,  usually  one  part  by  volume 
to  three  or  four  of  soil,  are  used  in  the  preparation  of  the  soil  for 
growing  greenhouse  roses.  Natural  manures  are  also  used  for  mulches. 
Thus  the  supply  of  sulfur  in  the  original  loam,  supplemented  by  heavy 
applications  of  organic  matter,  was  evidently  sufficient  for  maximum 
growth  of  roses.  As  it  is  everywhere  the  custom  to  use  natural  manures 
freely  in  the  preparation  of  such  soils,  this  result  is  likely  to  be  gen- 
erally applicable  as  far  as  greenhouse  rose  soils  are  concerned. 

EXPERIMENTS  WITH  CARNATIONS 

Profitable  Increases  Secured  From  Use  of  Acid  Phosphate 
in  1916-1917 

Tests  with  carnations  were  arranged  on  a  fairly  large  scale  in 
order  to  check  the  results  obtained  with  acid  phosphate  in  earlier 
work.2  In  1916-17,  with  a  comparatively  large  number  of  plants,  prof- 
itable increases  in  yields  of  carnations  were  again  obtained  where  acid 


94 


BULLETIN  No.  299 


[November, 


phosphate  was  used.    In  later  experiments  with  fewer  plants  of  each 
variety  the  results  were  not  conclusive. 

For  this  experiment  with  carnations  720  plants  of  the  variety 
Champion  were  set  in  the  two  south  benches  of  the  greenhouse,  and 
720  plants  of  the  variety  White  Enchantress  were  set  in  the  two  north 
benches.  Each  bench  was  divided  into  18  five-foot  sections  and  each 
section  contained  20  plants.  At  the  two  ends  of  each  of  the  four 
benches  sections  were  reserved  as  checks,  and  no  records  were  taken 
of  the  plants  growing  in  this  soil.  The  sections  were  separated  by  two 
cross  boards  set  about  one  inch  apart. 


TABLE  7. — INFLUENCE  OF  ACID  PHOSPHATE  ON  FLOWER  PRODUCTION  OF 
CARNATIONS,  1916-1917 


Variety 

Treatment 

Number 
of  plants 

Flowers 
per  plant 

Average 
flower 
diameter 

Average 
stem 
length 

Champion  

No  phosphate  

354 

20  .  62  ±  .  16 

inches 
2.86 

inches 
17.33 

White 

Acid  phosphate  
No  phosphate  

350 
345 

21.66±.17 
19.  27  ±  .13 

2.84 
3.58 

17.53 
17.72 

Acid  phosphate  

356 

20.65±.14 

3.56 

17.84 

Brown  silt  loam  soil  5  inches  deep  was  used  in  the  benches. 
Rotted  stable  manure  was  added  to  the  soil  of  all  sections  at  the  rate 
of  100  pounds  per  100  square  feet  of  bench  space,  and  dried  blood  at 
the  rate  of  3  pounds  per  100  square  feet  before  the  plants  .were  set  in 
the  bench.  Later  in  the  year  manure  mulches  and  applications  of 
dried  blood  at  the  same  rate  were  made  in  uniform  amounts  for  all 
sections  as  often  as  was  necessary.  Acid  phosphate  was  applied  to  all 
even-numbered  sections  at  the  rate  of  40  pounds  per  100  square  feet. 
This  was  applied  after  the  manure  and  dried  blood  had  been  thoroly 
incorporated  in  the  soil.  No  acid  phosphate  was  added  to  the  soil  in 
the  odd-numbered  sections. 

The  plants  were  fairly  uniform  and  apparently  free  from  disease 
when  set  into  the  soil  on  August  4.  During  the  growing  period  in  the 
greenhouse,  however,  a  number  of  plants  were  lost  as  the  result  of  stem 
rot,  so  that  there  remained  at  the  end  of  the  season  a  total  of  704 
plants  of  the  variety  Champion  and  701  of  White  Enchantress.  The 
flowers  were  picked  each  working  day  from  September  15  to  June  1. 
Records  were  made  of  the  number  of  flowers  from  each  plant,  flower 
diameter,  quality  of  flower,  and  stem  length. 

An  increase  in  the  number  of  flowers  was  obtained,  under  the  con- 
ditions of  the  experiment,  by  supplementing  manure  with  acid  phos- 
phate (Table  7,  Fig.  3).  The  differences  in  yield  amounted  to  1.0 
flower  a  plant  (5  percent)  with  Champion  and  1.4  flowers  a  plant 


1937] 


FERTILIZERS  FOR  ROSES  AND  CARNATIONS 


95 


(7.2  percent)    with  White  Enchantress.     There  were  no  differences 
in  quality  of  the  flowers  as  measured  by  diameter  and  stem  length. 


50 


Acid  Phosphate. 
A/o  Phosphate 


Date-  s/jo 7^5, 


Champion  Carnations 


U/JO 


//&/ 


2/28  Jftl 


4/30 


ISO 


•s 


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1 50 


*iite  Enchantress 
Carnations 


>L; 


.Acid  Phosphate 
.A/o  Phosphate 


~iijx>      e/J/         //si        2/20       3/31       5/53       s/j/ 
FIG.  3. — EFFECT  OF  ACID  PHOSPHATE  ON  CARNATION  YIELDS 

The  differences  in  favor  of  acid  phosphate  were  about  5  percent  and  7  percent  with 
Champion  and  White  Enchantress  respectively.  About  35  percent  of  the  crop  of  Champion 
was  picked  during  December  to  February  inclusive,  and  about  40  percent  of  the  crop  of  White 
Enchantress  was  picked  in  the  same  period. 


As  White  Enchantress  is  very  susceptible  to  splitting,  a  record 
was  kept  of  the  number  of  split  calyces  in  the  different  treatments. 
The  number  of  flowers  with  split  calyces  from  plants  in  the  sections 
treated  with  acid  phosphate  was  12.3  percent,  and  the  number  from  the 
sections  not  receiving  acid  phosphate  was  11.2  percent  of  the  total  cut 
from  the  respective  treatments.  This  is  too  small  a  difference  to  be 
considered  significant. 


96 


BULLETIN  No.  299 


Later  Experiments  with  Phosphorus  Not  Conclusive 

Fertilizer  work  with  carnations  was  resumed  in  1921.  For  three 
seasons  soil  plots  were  arranged  which  contained  phosphates  and  sul- 
fur fertilizers  in  varying  amounts.  No  definite  conclusions  in  favor  of 
any  of  the  treatments  could  be  drawn  from  these  tests. 

The  experiments  were  conducted  on  two  benches  adjacent  to  the 
south  bench  in  an  east-and-west  house.  Sixteen  6-foot  plots,  each 


TABLE  8. — KINDS  AND  AMOUNTS  OP  PHOSPHORUS 

AND  SULFUR  FERTILIZERS  USED  WITH 

CARNATIONS,   1921-1924 


Plot 

Fertilizer 

Pounds  per  100 
square  feet  of 
bench 

1 

1921-22 
Steamed  bone  

23.5 

2 

Acid  phosphate  

12.5 

3 

Ammonium  sulf  ate  

12 

4 

Control  

5 

Gypsum  

18.5 

6 

Potassium  sulfate     

16.5 

7 

Acid  phosphate  

18.5 

g 

Steamed  bone  

23.5 

9 

Precipitated  phosphate  

23.5 

10 

Gypsum  

18  5 

11 

Potassium  sulfate  

16.5 

12 

Acid  phosphate  

25 

13 

Sulfur  

25 

14 

Ammonium  sulfate  

12 

15 

Precipitated  phosphate  

11.5 

16 

Gypsum  

23 

1 

1922-23 

5 

2 

Acid  phosphate  

10 

3 

Gypsum  

10 

4 

Control   

5 

Gypsum  

20     • 

6" 

4 

9 

Precipitated  phosphate     

4 

10 

Gypsum  

10 

11 

Steamed  bone  

5 

12 

Acid  phosphate  

10 

13 

Gypsum  

18 

14 

Control  

1 

1923-24 
Control  

0 

2 

21 

3 

Precipitated  phosphate     

10 

4 

Apid  phosphate  

17 

5 

Gypsum  

8 

6 

Sulfur  

2 

7" 

34 

10 

Ac'd  phosphate  

34 

11 

Sulfur  

2 

12 

Gypsum  

8 

13 

Acid  phosphate  

17 

14 

10 

15 

21 

16 

Control  

•In  1922-23  Plots  7,  8,  15,  and  16  and  in  1923-24  Plots  8  and  9  were 
not  used  in  this  experiment. 

containing  24  plants,  were  set  off  by  cross  partitions.  The  plots  were 
numbered  consecutively,  beginning  at  the  east  end  of  the  south  bench. 
The  initial  steps  in  preparing  the  soil  were  similar  to  those  with  roses. 
Fresh  soil  was  used  each  season,  the  commercial  fertilizers  being  in- 
corporated just  before  setting  the  plants. 


1927] 


FERTILIZERS  FOR  ROSES  AND  CARNATIONS 


97 


Laddie  carnations  were  transplanted  from  the  field  about  the  first 
week  in  August.  During  the  growing  season  temperatures  were  main- 
tained as  follows:  night,  52°  F.,  day,  58°  F.,  except  on  bright  days, 
when  the  temperature  rose  to  63-68°.  The  seasons  of  record  were  as  fol- 
lows: 1921-1922,  September  28  to  March  16;  1922-23,  October  3  to 
March  26;  1923-24,  September  26  to  April  16.  Thruout  the  experi- 
ments note  was  made  of  split  calyces  in  order  to  determine  their  rela- 
tion, if  any,  to  fertilizer  treatment.  Measurement  of  stem  lengths  and 
flower  diameters  began  about  the  first  of  November. 

The  first  season  all  carnation  plots  received,  in  addition  to  manure, 
dried  blood  at  the  rate  of  1.5  pounds  per  100  square  feet,  except  where 
ammonium  sulfate  was  used.  The  second  season  2  pounds  and  the 
third  season  8  pounds  of  dried  blood  were  used  per  100  square  feet  of 
bench.  The  kinds  and  rates  of  application  of  other  materials  used 
each  year  are  shown  in  Table  8.  These  fertilizers  were  usually  worked 
into  the  soil  just  before  benching  the  plants.  In  1923  this  plan  was 
varied  in  that  half  the  plots  (Nos.  10  to  16)  received  fertilizer  when 
the  plants  were  benched  July  29,  and  duplicate  treatments  were  ap- 
plied to  the  remaining  plots  (Nos.  1  to  7)  September  21,  after  the 
plants  were  well  established. 

The  increases  in  number  of  flowers  obtained  with  the  phosphate 
fertilizers  were  not  large  enough  to  be  considered  with  certainty 
as  resulting  from  the  fertilizer  treatment  (Table  9).  The  low 
yields  with  ammonium  sulfate  and  potassium  sulfate  in  1921-22  were 
doubtless  the  results  of  the  use  of  excess  amounts  of  fertilizer.  In 
1923-24  the  time  of  application  of  the  fertilizers  made  no  differences 
in  the  yields.  The  average  yield  a  plant  on  plots  receiving  fertilizers 
in  July  was  6.21  ±.10,  and  on  plots  receiving  similar  applications  in 
September  the  yield  averaged  6.27 ±.10  flowers  a  plant. 

TABLE  9. — EFFECT  OF  PHOSPHORUS  AND  SULFUR  FERTILIZERS  ON  PRODUCTIVENESS 

OF  LADDIE  CARNATIONS 


Fertiliser 

Season 

Number 
of  plants 

Flowers 
per  plant 

Average 
flower 
diameter 

Average 
stem 
length 

Control  

1921-22 

26 

7.08±  .25 

inches 
3.53 

inches 
19  99 

Acid  phosphate  

1922-23 
1923-24 
1921-22 

48 
48 
73 

6.46±.19 
6.29±.19 
7  .  60  ±  .  18 

3.38 
3.44 
3.48 

19.26 
21.73 
19  54 

Steamed  bone  

1922-23 
1923-24 
1921-22 

48 
91 
47 

6.83±.19 
6.12±.14 
6  66  ±    17 

3.38 
3.50 
3  46 

19.03 
21.43 
19  88 

Precipitated  phosphate  

1922-23 
1923-24 
1921-22 

48 
48 
48 

6.52±  .20 
6.62±.17 
6  73  ±    19 

3.32 
3.30 
3  52 

19.23 
20.82 
20  35 

Gypeum  

1922-23 
1923-24 
1921-22 

47 
48 
72 

6.81±.20 
6.02±.18 
7  04  ±  .  16 

3.33 
3.29 
3  53 

18.94 
21.58 
19  94 

Ammonium  sulfate  

1922-23 
1923-24 
1921-22 

96 
48 
34 

6.62±.14 
6.52±.19 
3.00±  .36 

3.37 
3.54 
3  26 

19.04 
21.23 
13  95 

Potassium  sulfate  

1921-22 

37 

4  83  ±   29 

3  31 

16  58 

Sulfur  

1923-24 

47 

5.94±.18 

3.54 

21.30 

98 


BULLETIN  No.  299 


[November, 


Steamed  bone  was  no  more  efficient  than  acid  phosphate,  and  at 
the  rates  used  the  cost  of  bone  meal  was  as  high  or  higher. 

The  actual  yields  on  the  plots  where  gypsum  was  used  were 
slightly  higher  on  the  average  than  on  the  check  plots.  They  were 
lower,  however,  than  with  acid  phosphate,  and  no  definite  conclusions 
can  be  drawn  with  such  results  as  a  basis.  In  the  case  of  the  other 
sulfur-bearing  materials,  excess  amounts  were  no  doubt  responsible 
for  decreased  yields. 

No  consistent  relation  between  fertilizer  treatment  and  the  occur- 
rence of  split  calyces  was  noted  in  these  experiments  (Table  10) . 


TABLE  10. — PERCENTAGES  OF  FLOWERS  WITH  SPLIT  CALYCES  ON  LADDIE  CARNATION 

PLOTS 


Fertilizer 

1921-22 

1922-23 

1923-24 

Total 
flowers 

Split 
flowers 

Total 
flowers 

Split 
flowers 

Total 
flowers 

Split 
flowers 

Control  

147 
446 
286 
255 
435 
62 
148 

perct. 
12.2 
13.7 
11.5 
19.6 
17.2 
32.2 
19.6 

280 
258 
281 
268 
562 

perct. 
12.1 
27.1 
13.2 
17.2 
16.5 

273 
527 
608 
594 
273 

257 

perct. 
9.5 
10.6 
5.3 
5.2 
8.8 

6.9 

Acid  phosphate   

Steamed  bone  

Precipitated  phosphate  

Gypsum  

Ammonium  sulf  ate  

Potassium  sulf  ate  

Sulfur  

In  1925-26  an  attempt  was  made  to  determine  whether  there  are 
any  differences  in  the  response  of  different  varieties  of  carnations  to 
phosphatic  fertilizers.  Twelve  varieties  were  planted  and  various  fer- 
tilizers applied.  Records  of  flower  production  were  kept  from  October 
15  to  April  15.  The  results  wrere  so  irregular  that  no  definite  compari- 
sons were  possible  (Table  11).  As  a  test  of  the  effect  of  different  fer- 
tilizers on  flower  production,  the  results  of  this  test  have  little  or  no 
value.  The  yields  obtained  from  the  check  plots  were  as  good  as  or 
better  than  those  from  the  heavily  fertilized  plots.  It  is  quite  likely  that 
the  concentration  of  salts  in  the  soil  was  too  high. 


1927] 


FERTILIZERS  FOR  ROSES  AND  CARNATIONS 


99 


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100  BULLETIN  No.  299  [November, 

CONCLUSIONS  AND  RECOMMENDATIONS 

Acid  phosphate,  used  to  supplement  manure  and  dried  blood,  is 
particularly  effective  in  increasing  the  productiveness  of  greenhouse 
roses.  It  may  also  prove  effective  with  carnations,  tho  increases' in 
yield  are  likely  to  be  less  marked. 

Increases  in  the  number  of  roses  or  carnations  resulting  from  the 
use  of  acid  phosphate  are  not  accompanied  by  decreased  length  of 
stem  or  size  of  flower. 

Acid  phosphate  is  much  more  effective  and  more  economical  for 
greenhouse  use  than  is  steamed  bone  meal. 

Annual  applications  of  about  25  pounds  of  acid  phosphate  to  100 
square  feet  of  bench  are  recommended  as  being  probably  near  the 
optimum,  at  least  for  roses,  in  most  greenhouse  soils.  As  much  as  40 
pounds  may  be  used  without  danger  of  overfeeding. 

No  beneficial  effects  on  flower  production  are  likely  to  result 
ordinarily  from  the  use  of  sulfur-bearing  commercial  fertilizers  in 
greenhouse  soils. 

LITERATURE  CITED 

1.  Lumsden,  David.  Fertilizers  for  carnations.  N.  H.  Agr.  Exp.  Sta.  Bui.  159.  1912. 

2.  Dorner,  H.  B.,  Muncie,  F.  W.,  and  Nehrling,  A.  H.  The  use  of  commercial 

fertilizers  in  growing  carnations.    111.  Agr.  Exp.  Sta.  Bui.  176.  1914. 

3.  Muncie,  F.  W.    The  use  of  commercial  fertilizers  in  growing  roses.    111.  Agr. 

Exp.  Sta.  Bui.  196.  1917. 

4.  White,  Thomas  H.     Experiments  with  fertilizers  on  greenhouse  crops.     Md. 

Agr.  Exp.  Sta.  Bui.  222.    1918. 

5.  Pember,  F.  R.s  and  Adams,  G.  E.    A  study  of  the  influence  of  physical  soil 

factors  and  of  various  fertilizer  chemicals  on  the  growth  of  the  carna- 
tion plant.    R.  I.  Agr.  Exp.  Sta.  Bui.  187.    1921. 

6.  Olson,  Geo.  A.,  and  St.  John,  J.  L.  An  investigation  of  sulfur  as  a  plant  food. 

Wash.  Agr.  Exp.  Sta.  Bui.  165.    1921. 

7.  Crocker,  Wm.    The  necessity  of  sulfur  carriers  in  artificial  fertilizers.    Jour 

Am.  Soc.  Agron.    15,  129-141.    1923. 

8.  Powers,  W.  L.     Sulfur  in  relation  to  soil  fertility.    Ore.  Agr.  Exp.  Sta.  Bui. 

199.    1923. 

9.  Stewart,  Robert.    Sulfur  in  relation  to  soil  fertility.    111.  Agr.  Exp.  Sta.  Bui. 

227.    1920. 

10. .   Sulfur  and  soil  fertility.   Florists'  Rev.  56,  no.  1431,  35.    1925. 

11.  Babcock,   E.  B.,   and  Clausen,   R.   E.     Genetics  in  relation  to   agriculture. 

McGraw-Hill.  1918. 


19S7} 


FERTILIZERS  FOR  ROSES  AND  CARNATIONS 


101 


APPENDIX 

In  fertilizer  experiments  factors  other  than  those  under  investi- 
gation exert  an  important  influence  on  the  observed  results.  The  in- 
herent variability  of  the  plants  and  differences  in  soil  and  other  envi- 
ronmental conditions  between  plots  all  have  their  effects.  Under  such 
conditions  the  "probable  error"  of  the  mean  is  a  useful  aid  in  draw- 
ing conclusions. 

TABLE  12. — MEANS,  STANDARD  DEVIATIONS,  COEFFICIENTS  OF  VARIABILITY,  AND 

COEFFICIENTS  OF  CORRELATIONS  DERIVED  FROM  THE  DATA  ON  FLOWER 

PRODUCTION  OF  ROSES,  TABLES  15  TO  19 


Variety 

Treatment 

Year 

Mean 

Standard 
deviation 

Coefficient 
of 
variability 

No  phosphate  

1916-17 

18.10±  .28 

5.05±   20 

27.90 

Acid  phosphate  

1917-18 
1918-19 

1916-17 

15.00±.25 
13.94±.25 

18.20±  .33 

4.46±.26 
4.  40  ±.17 

5.75±  .23 

29.73 
31.50 

31  60 

Ophelia          

No  phosphate  

1917-18 
1918-19 

1916-17 

17.01±.31 
15.71±.33 

32.12±  .42 

5.70±.23 
5.80±.23 

7.46±  .30 

33.50 
36.90 

23.10 

Acid  phosphate  

1917-18 
1918-19 

1916-17 

25.01±.36 
25.  57  ±.38 

35.21±  .47 

6.41±.25 
6.80±.27 

8.35±  .33 

25.62 
26.60 

23.55 

No  phosphate  .... 

1917-18 
1918-19 

1916-17 

27.68±.40 
27.86±.41 

36.56±  .69 

7.15±.28 
7.30±.29 

8  28  ±   33 

25.83 
26.20 

22  65 

White  Killarney  

Acid  phosphate  
No  phosphate  

1917-18 
1918-19 

1916-17 
1917-18 
1918-19 

1916-17 

36.  44  ±.44 
35.53±.48 

39.20±.60 
39.08±.53 
36.82±.60 

33.80±  .41 

7.90±.31 
8.50±.34 

7.20±.28 
9.52±.38 
10.70±.43 

7.24±  .86 

21.67 
23.90 

18.38 
24.36 
29.10 

21.40 

Tfillfirnpy 

• 
Acid  phosphate  

Steamed  bone  

1917-18 
1918-19 

1916-17 
1917-18 
1918-19 

1916-17 

32.89±.36 
34.56±.43 

35.90±.48 
36.40±.49 
36.87±.55 

34  90  ±    58 

6.41±.25 
7.60±.30 

8.54±.34 
8.96±.36 
9.80±.39 

10  35  ±   41 

19.48 
21.90 

23.80 
24.61 
26.50 

29  65 

Richmond  

Acid  phosphate  
Steamed  bone  

1916-17 

45.20±.60 
28  30  ±   39 

10.70±.42 
6  87  ±   27 

23.00 
24.25 

Acid  phosphate  

35.45±.56 

9.89±.39 

27.90 

In  the  experiments  described  in  this  bulletin  the  yields  of  flower 
crops  were  highly  variable,  altho  environmental  conditions  were  main- 
tained as  uniform  as  is  possible  under  ordinary  greenhouse  conditions. 
It  is  important,  therefore,  that  ample  allowance  be  made  for  variabil- 
ity in  drawing  conclusions.  Detailed  data  on  flower  production  by 
roses  and  carnation  plants  are  given  in  the  frequency  tables  (Tables 
15  to  20) .  The  means,  standard  deviations,  and  coefficients  of  variabil- 
ity computed  from  these  data  are  shown  in  Tables  12  and  13. 

It  was  thought  that  there  might  be  a  correlation  between  the  num- 
ber of  flowers  produced  by  the  plant  and  length  of  flower  stems,  and 


102 


BULLETIN  No.  299 


[November, 


TABLE  13. — MEANS,  STANDARD  DEVIATIONS,  AND  COEFFICIENTS  OF  CORRELATION 
DERIVED  FROM  THE  DATA  ON  FLOWER  PRODUCTION  OF  CARNATIONS,  TABLE  20 


Variety 

Treatment 

Mean 

Standard 
deviation 

Coefficient  of 
variability 

Champion  

No  phosphate  

20  .  62  ±  .  16 

4  57  ±    12 

22  21 

Acid  phosphate  

21.66±  .17 

4.  78  ±  .12 

22.06 

White  Enchantress.  .  . 

No  phosphate  

19.  27  ±  .13 

3.64±  .09 

18.89 

Acid  phosphate  

20.651.14 

3.96±.10 

19.17 

also  that  there  might  exist  a  greater  correlation  of  this  sort  in  the 
acid-phosphate  series  than  in  the  no-phosphate.  Thus  the  excess  of 
production  in  the  first  series  might  simply  represent  a  larger  number 
of  short-stemmed  flowers.  This  obviously  would  not  be  desirable 
from  the  standpoint  of  the  florist.  The  relation  between  yield  and 
stem  length,  as  indicated  by  the  correlation  coefficient,  r,  is  shown  for 
three  varieties  of  roses  in  Table  14. 

The  correlation  coefficients  are  very  small,  in  many  cases  too  small 
in  relation  to  the  probable  error  to  be  considered  at  all  significant. 
From  these  data  it  appears  that  there  was  little  or  no  relation  between 
the  number  of  flowers  produced  by  a  plant  and  the  stem  lengths.  The 
two  characters  varied  practically  independently.  Stem  lengths  did 
not  decrease  consistently  with  increased  yields  by  the  plants.  Since 
this  was  true  regardless  of  fertilizer  treatment,  there  was  no  error  from 
this  source  to  impair  the  value  of  the  data  on  flower  production  with 
and  without  acid  phosphate. 


TABLE  14. — CORRELATION  BETWEEN  NUMBER  OF  FLOWERS  AND 
STEM  LENGTH  IN  ROSES 


Variety 

Treatment 

Year 

Coefficient  of 
Correlation 

1916-17 

r 
—  .112±  .013 

Acid  phosphate  

1917-18 
1918-19 
1916-17 

-.079±.014 
-.064±.015 
—  .045±  .013 

No  phosphate  

1917-18 
1918-19 
1916-17 

-.030±.014 
-.010±  .014 
—  .092±    Oil 

1917-18 
1918-19 
1916-17 

.006±.011 
-.036±  .011 
—   060  ±   010 

No  phosphate  

1917-18 
1918-19 
1916-17 

-.007  ±.011 
-.045±  .011 
—  062  ±    009 

Acid  phosphate  

1917-18 
1918-19 
1916-17 

-.012±.009 
-.061±.010 
—  096  ±   009 

White  Killarney 

No  phosphate  

1917-18 
1918-19 
1916-17 

-.048±.009 
-.065±.009 
—  021  ±   010 

1916-17 

—  042  ±    009 

Killarney  

Steamed  bone  
Acid  phosphate  

1916-17 
1916-17 

-.081  ±.009 
—  .057+    008 

Richmond  

Steamed  bone  
Acid  phosphate  

1916-17 
1916-17 

-.052±  .010 
-.010±  .009 

19S7] 


FERTILIZERS  FOR  ROSES  AND  CARNATIONS 


103 


TABLE  15. — FREQUENCY  TABLES  SHOWING  VARIABILITY  IN  FLOWER 
PRODUCTION  BY  OPHELIA  ROSES 


Number  of  plants 

Flowers 
per  plant 

No  phosphate 

Acid  phosphate 

1916-17 

1917-18 

1918-19 

1916-17 

1917-18 

1918-19 

1-5 

1 

1 

6-10 

"l 

"l 

11-15 

5 

"t 

5 

"| 

16-20 

"ft 

29 

19 

'*2 

12 

18 

21-25 

21 

47 

43 

12 

41 

35 

26-30 

36 

35 

40 

23 

38 

34 

31-35 

36 

18 

23 

36 

26 

29 

36-40 

29 

7 

7 

36 

14 

21 

41-45 

12 

2 

2 

16 

7 

2 

46-50 

5 

12 

1 

51-55 

4 

56-60 

1 

61-65 

1 

TABLE  16. — FREQUENCY  TABLES  SHOWING  VARIABILITY  IN  FLOWER  PRODUCTION 

BY   KlLLARNEY  ROSES 


Number  of  plants 


Flowers 
per  plant 

No  phosphate 

Acid  phosphate 

1916-17 

1917-18 

1918-19 

1916-17 

1917-18 

1918-19 

16-20 

1 

1 

2 

21-25 

7 

10 

13 

2" 

7 

15' 

26-30 

22 

26 

27 

17 

22 

16 

31-35 

34 

36 

38 

25 

24 

26 

36-40 

31 

28 

33 

43 

25 

30 

41-45 

24 

26 

15 

28 

23 

25 

46-50 

16 

8 

8 

21 

22 

12 

51-55 

6 

9 

5 

8 

14 

8 

56-60 

2 

1 

2 

4 

8 

61-65 

1 

2 

1 

1 

66-70 

•  .  . 

2 

71-75 

1 

TABLE  17. — FREQUENCY  TABLES  SHOWING  VARIABILITY  IN  FLOWER  PRODUCTION 
BY  KlLLARNEY  AND  RICHMOND  ROSES,  1916-1917 


Number  of  plants 


Flowers 
per  plant 

Killarney 

Richmond 

Steamed  bone 

Acid  phosphate 

Steamed  bone 

Acid  phosphate 

13-17 

8 

1 

4 

5 

18-22 

5 

3 

30 

9 

23-27 

22 

2 

30 

15 

28-32 

26 

12 

43 

24 

33-37 

30 

15 

25 

37 

38-42 

22 

25 

9 

19 

43-47 

13 

28 

1 

20 

48-52 

10 

18 

2 

10 

53-57 

5 

23 

2 

58-62 

2 

11 

1 

63-67 

1 

5 

2 

68-72 

73-77 

78-82 

"l 

104 


BULLETIN  No.  299 


TABLE  18. — FREQUENCY  TABLES  SHOWING  VARIABILITY  IN  FLOWER 
PRODUCTION  BY  HOOSIER  BEAUTY  ROSES 


Flowers 

Number  of  plants 

per  plant 

No  phosphate 

Acid  phosphate 

1916-17 

1917-18 

1918-19 

1916-17 

1917-18 

1918-19 

1-5 

1 

2 

1 

3 

2 

6-10 

7 

17 

17 

'l3 

17 

26 

11-15 

29 

62 

72 

33 

37 

46 

16-20 

66 

48 

40 

45 

45 

40 

21-25 

31 

14 

12 

39 

34 

24 

26-30 

8 

| 

2 

7 

6 

4 

31-35 

2 

3 

2 

2 

36-40 

1 

... 

TABLE  19. — FREQUENCY  TABLES  SHOWING  VARIABILITY  IN  FLOWER  PRODUCTION 
BY  WHITE  KILLARNEY  ROSES 


Number  of  plants 


Flowers 
per  plant 

No  phosphate 

Acid  phosphate 

1916-17 

1917-18 

1918-19 

1916-17 

1917-18 

1918-19 

11-15 

2 

1 

16-20 

8 

"3 

"3 

7 

"e 

"l 

21-25 

15 

13 

9 

12 

8 

8 

26-30 

28 

40 

34 

24 

22 

16 

31-35 

35 

34 

36 

26 

30 

25 

36-40 

33 

39 

31 

40 

31 

31 

41-45 

15 

13 

19 

18 

26 

18 

46-50 

8 

1 

11 

11 

14 

17 

51-55 

1 

1 

5 

6 

8 

56-60 

J 

6 

61-65 

4 

TABLE  20.- 


-FREQUENCY  TABLES  SHOWING  VARIABILITY  IN  FLOWER  PRODUCTION 
BY  CARNATIONS 


Number  of  plants 


Flowers 
per  plant 

Champion 

White  Enchantress 

No  phosphate 

Acid  phosphate 

No  phosphate 

Acid  phosphate 

10 

1 

( 

11 

2 

"3 

3 

12 

5 

4 

3 

'  1 

13 

9 

3 

6 

14 

10 

13 

14 

"i 

15 

20 

10 

23 

12 

16 

25 

13 

31 

28 

17 

17 

22 

46 

22 

18 

31 

29 

31 

37 

19 

36 

24 

35 

50 

20 

28 

34 

39 

49 

21 

27 

19 

19 

25 

22 

29 

29 

19 

30 

23 

21 

28 

34 

20 

24 

18 

23 

15 

17 

25 

24 

24 

5 

12 

26 

12 

13 

11 

13 

27 

15 

19 

3 

6 

28 

7 

11 

5 

7 

29 

5 

9 

2 

5 

30 

3 

7 

6 

31 

4 

4 

3 

32 

1 

3 

1 

3 

33 

2 

2 

2 

34 

1 

1 

35 

1 

2 

36 

1 

UNIVERSITY  OF  ILLINOIS-URBANA 

Q.630.7IL6B  C002 

BULLETIN.  URBANA 
295-3121927-28 


